React Native debugger not working

when i try to debug my react native app, intellij tells me

```/home/seunlanlege/.nvm/versions/node/v6.12.2/bin/node --debug-brk=39179 --expose_debug_as=v8debug /home/seunlanlege/idea-IU-173.3942.27/plugins/JavaScriptDebugger/proxy/launcher.js --port=8081 --sourcesStoragePath=/home/seunlanlege/Projects/Vesnet/.tmp/reactNativeBuild
Debugger listening on [::]:39179
[intellij] Downloaded debuggerWorker.js (Logic to run the React Native app) from the Packager.

[intellij] Starting debugger app worker.

[intellij] Established a connection with the Proxy (Packager) to the React Native application

[intellij] Debugging session started successfully.

[intellij] [Warning] Failed to prepare the JavaScript runtime environment. Message:
[object Object]. Debugging won't work: Try reloading the JS from inside the app, or Reconnect the debugger: Unexpected token <

[intellij] [Warning] Failed to prepare the JavaScript runtime environment. Message:
[object Object]. Debugging won't work: Try reloading the JS from inside the app, or Reconnect the debugger: Unexpected token <

[intellij] [Warning] Failed to prepare the JavaScript runtime environment. Message:
[object Object]. Debugging won't work: Try reloading the JS from inside the app, or Reconnect the debugger: Unexpected token <

[intellij] [Warning] Failed to prepare the JavaScript runtime environment. Message:
[object Object]. Debugging won't work: Try reloading the JS from inside the app, or Reconnect the debugger: Unexpected token <

[intellij] [Warning] Failed to prepare the JavaScript runtime environment. Message:
[object Object]. Debugging won't work: Try reloading the JS from inside the app, or Reconnect the debugger: Unexpected token <
```

any ideas how to solve this?